In a field of general industrial equipment, a mechanical control element is driven by an electric motor. In recent years, so-called electrically mechanically integrated electric drive device, which is configured such that an electronic control unit formed from a semiconductor element etc. controlling a rotation speed and/or a rotation torque of the electric motor is integrally mounted in the electric motor, has been used.
As an example of the electrically mechanically integrated electric drive device, for instance, an electric power steering device is configured such that a turning direction and a turning torque of a steering shaft that turns by driver's operation of a steering wheel are detected, and on the basis of these detection values, the electric motor is driven so as to rotate in the same direction as the turning direction of the steering shaft, then a steering assist torque is generated. To control this electric motor, the power steering device is provided with an electronic control unit (ECU: Electronic Control Unit).
As a related art electric power steering device, for instance, an electric power steering device disclosed in Japanese Unexamined Patent Application Publication No. 2013-060119 (Patent Document 1) is known. Patent Document 1 discloses the electric power steering device configured by an electric motor unit and an electronic control unit. An electric motor of the electric motor unit is housed in a motor housing having a cylindrical portion that is made of aluminum alloy etc. Boards (substrates) on which electronic elements or components of the electronic control unit are mounted are housed in an ECU housing that is located on an opposite side to an output shaft of the motor housing in an axial direction of the motor housing. The boards housed in the ECU housing are provided with a power supply circuit unit, a power conversion circuit unit having a power switching element such as a MOSFET and an IGBT that drive and control the electric motor, and a control circuit unit that controls the power switching element. Output terminals of the power switching element and input terminals of the electric motor are electrically connected through a bus bar.
Power is supplied to the electronic control unit housed in the ECU housing from a power supply through a connector terminal assembly made of synthetic resin. Further, detection signals concerning an operating state etc. are sent to the electronic control unit from detection sensors. The connector terminal assembly functions as a lid member or a cover member, and is connected to the electronic control unit so as to cover an opening formed at the ECU housing. The connector terminal assembly is fixed to an outer surface of the ECU housing with fixing bolts.
As another electric drive device configured such that the electronic control unit and the electric motor unit are integrated, electric brake and an electric hydraulic pressure controller for a various kinds of hydraulic pressure control are known.